Today's laundry detergents are available in a dizzying array of options. Consumers have the choice of liquids or powders, scented or fragrance-free, and green or conventional products. Additionally, many manufacturers offer two distinct types of laundry detergent for the two different types of washing machines -- standard top-loading appliances and high-efficiency (HE) models. HE washers use less water; therefore, their detergents must be less sudsy to prevent soap residue on clothing. It's important to note that a few detergents are formulated to work in both types of machines (you just use less soap for HE machines).
A detergent's stain-fighting ability is another factor to consider. Overall, reviewers strongly recommend detergents that are effective on a wide range of stains, rather than those that claim to erase only certain compounds like blood or wine.
In our quest to uncover the best evaluations, we sifted through several sources. ConsumerReports.org publishes the best review of laundry detergents, with an evaluation of 31 standard and 13 HE detergents. Editors apply nine common stains -- including grass, chocolate, red wine and blood -- onto cotton swatches and wash them in warm water. The washed swatches are then run through a machine to evaluate and detect any leftover residue. This publication's laundry detergent buying guide also offers tips, such as avoiding a detergent with a fabric softener on children's pajamas because "it's been shown to reduce flame resistance."
Good Housekeeping magazine editors also evaluate nine laundry detergents. Testers apply 15 stains, including blood, coffee and ink, to two types of fabrics -- cotton and polyester. They allow the stains to set for 24 hours and then wash them in different detergents at two temperatures -- the cotton is washed in hot water and polyester in cold. Only their top pick and best budget brands are ultimately identified; editors don't identify the other products tested.
At eco-focused Grist.org, Sarah van Schagen tests six green detergents -- products that do not contain surfactant nonylphenol ethoxylate (NPE), phosphates or bleach as well as items that are free of perfumes and dyes. (Surfactants like NPE help cleaning agents better penetrate fabric and remove dirt, but they have been shown to be harsh on the environment.) Schagen applies ketchup, balsamic vinaigrette, blueberries and red wine to the front of several cotton T-shirts, and she applies mud to their backs. After washing each T-shirt in one of the detergents, she evaluates which do the best job of minimizing stains.
Additionally, National Geographic's TheGreenGuide.com includes a detergent buying guide in its summer 2008 print issue. This article offers useful information for determining whether a detergent is eco-friendly. Although nine detergents are ultimately recommended by editors, there isn't any testing to see how well each product actually works.
An Australian publication, Choice magazine, offers separate reviews for powder and liquid laundry detergents. Grass and tomato stains are used for stain analysis. Fabric swatches are washed in cold water and then scientifically evaluated to see how much material is removed. According to its experts, the best washing powders ultimately give a better wash than laundry liquids. Unfortunately, most of the products mentioned aren't sold in the U.S.
Consumer magazine, a New Zealand publication, also conducts its testing at the Choice magazine lab, using the same methodology and criteria. Editors compare 11 top- and front-loader powders and rate them on dirt and stain removal as well as on suitability for wastewater recycling (if the remaining water can be reused). Its recommended detergent, and most of the others in its evaluation, also aren't widely available in the U.S.
As always, consumer insights at Amazon.com, Drugstore.com and RateItAll.com also prove to be useful. However, we found that many owner reviews tend to focus on the detergent's scent rather than on its overall cleaning ability.
Cold-water washing can benefit the environment and be easier on your wallet because you're not using energy to heat water. Furthermore, laundry detergents, especially for lightly soiled loads, seem to work just as well in cold water as in hot. Due to this, an increasing number of specially formulated cold-water washing detergents have cropped up in recent years. Two noteworthy product lines, Tide and Cheer, have been particularly successful. In addition to causing less wear and fading on fabrics, Procter & Gamble, the maker of Tide, also claims that cold-water washing can save consumers up to $63 a year in energy costs -- because according to the U.S. Department of Energy, "90 percent of the energy used for washing clothes in a conventional top-load washer is for heating the water."
There are some caveats to cold-water washing, however. For most lightly soiled clothing, experts say this technique is fine. However, hot water is better for killing bacteria in heavier-soiled items like diapers and underwear and for killing dust mites in household linens and bedding.